His first animated appearances were on the Marvel Super Heroes Show, which aired in syndication in 1966 and featured five of Marvel's superheroes starring in their own series each one consisting of 13 episodes (separated into three 7-minutes long segments). This show had very limited animation, and was composed almost entirely of actual comic book panels with a voice-over; basically an early version of today's motion-comics. Loki (voiced by Len Carlson) is featured in the Mighty Thor segments; he appears in a total of 9 episodes and is the main anatagonist of the series, as well as one of the few recurring villains on the show (Amora the Enchantress and Skurge the Executioner both appear in two episodes, but only alongside Loki. Mr. Hyde is the other recurring villain, who appears in two episodes - and shares one episode with Loki. Hercules also appears in two episodes, but in his second appearance he is more of an ally to Thor than a foe). The first episode to feature the Loki was the series premiere, entitled "Trapped by Loki". At the beginning of the episode we find Loki imprisoned inside a tree; he was imprisoned there by Odin for all the evil he has done, and will remain there until one person would shead a tear for him. Loki imposes his will on the tree and manages to shake one of its branches until a leaf falls, landing into the eye of Heimdall who sheads a tear thus releasing Loki from his prison.

Now free, Loki plans on getting his revenge on the one who defeated him before, his half-brother the Mighty Thor, the God of Thunder. He travels to Earth where he starts causing mischief until Thor confronts him. Loki manages to hypnotize Thor, but is unable to take his hammer since Thor is the only one who can wield it. Thor breaks free from under Loki's control when, separated from his hammer for more than a minute, he transforms back into his mortal identity, Doctor Don Blake. Thor then defeats Loki and sends him back to Asgard where Odin forbids Loki from visitng Earth again - though obviously Loki goes against Odin's wishes, after he finds out Thor's secret mortal identity. He returns to Earth and once again confronts Thor; I find it weird that this time Loki disguised himself as an old man by wearing a fake beard, when in other episodes and even earlier during this very episode he was shown able to alter his appearance with magic, not with disguises. Once Thor is separated from his hammer and turns back into Don Blake, Loki conjures a force field around the hammer, so that no one (not even Thor) could touch it again. Don Blake tricks Loki into lifting this force field to check the hammer once he sees Thor with his weapon in his hands - in reality, a plastic dummy. Once the force field is lifted Don Blake takes back the hammer and turns into Thor. Loki is once again captured and taken in front of Odin who vows that Loki will not escape again.

Loki returns in the next episode, titled "Chained Evil". At the beginning of the episode we find Loki in Asgard, chained to a rock until the end of time as punishment for plotting against Thor. Wanting his revenge Loki uses his powers to attract Thor's enchanted hammer from Earth back to Asgard, smashing through his chains and freeing him in the process. Thor travels to Asgard trying to figure out what happened to his weapon; he soon finds himself trapped inside Loki's magic forest where the trees attack him, but he manages to defend himself with a quickly made wooden hammer. Loki confronts him, but Thor has regained his hammer and easily defeats him and brings him once again in front of Odin, who again forbids Loki to follow Thor back to Earth. This time however Loki does as he was told, but also plans on using one of his minions to fight Thor on Earth. He finds Sandu, Master of the Supernatural - a mentalist working at a carnival, and increases his extra-senzory powers to make him powerful enough to fight Thor. Sandu goes on a crime spree with his new found powers, and no one can stop him, apparently not even Thor. Pleading for help to his father Odin, Thor is given the Belt of Strength, which increases all of his powers in order to stop Sandu. At the climax of the battle, Sandu manages to trap Thor's hammer inside another dimmension, but when trying to lift it (something impossible for anyone other than Thor), he concentrates his powers too much causing a mental short-circuit, and is thus defeated.

In "Enchantress and Executioner", Odin wanting to end the romance between his son Thor and the mere mortal Jane Foster, starngely enough asks Loki for advice. Loki plans on sending Amora the Enchantress to Earth to make Don Blake/Thor fall in love with her, so that he will forget all about Jane. The plan backfires as Don Blake rejects her and Amora in turn asks Skurge the Executioner to come to Earth and destroy Jane Foster. However both of them are defeated rather easily by Thor. Next, Loki tricks Odin into traveling to Earth himself, to stop his son's love affair with a mortal. Odin agrees and leaves Loki in charge of Asgard while he is absent - something that shouldn't have happened considering the events from the previous two episodes. Once he sees himself on Odin's throne, Loki plans on remaining there forever and frees Skagg the Storm Giant and Surtur the Fire Demon on Earth hoping Odin would not return from this battle. The two evil gods are defeated by the combined forces of Odin, Thor and Balder after a very long fight. In the end, Odin banishes Loki to serve with the trolls (a reference to the mythical realm of Vanaheim, I think).

The episode titled "At the Mercy of Loki" marks his next appearance on this show. This time Loki travels to Earth and tries to dispose of Don Blake's cane (which turns into Thor's hammer when he transforms into the Thunder God), also kidnapping nurse Jane Foster and taking her to Asgard. Thor follows, and once he arrives in Asgard he fights Loki - his enchanted hammer against Loki's enchanted sword. Their battle is interrupted when Odin returns; Loki tricks him into believing Thor has brought the mortal woman he loves to Asgard to turn her into an immortal, against Odin's wishes. Thor is then challenged by Loki to the Trial of the Gods, but is allowed by Odin time to return Jane Foster to Earth. Odin then explains their trial: they must cross the deadly land of Skornheim without carrying any weapons, and the first one who returns will be considered the victor. Soon Thor learns that Loki broke the rules by bringing with him the magical Norn Stones, which gave him various abilities needed to pass the obstacles they encounter during their trial. Loki shows Thor a vision that he has sent the Enchantress and the Executioner to Earth to kill Jane; Odin learns of Loki's treachery and sends Balder the Brave to protect the nurse while Thor participates in the trial. Towards the end of their challenge, Thor and Loki are confronted by Yagg the invincible slayer of Skornheim - but while Loki uses a Norn Stone to escape, Thor defeats the warrior in combat. Loki arrives first in Asgard with Thor only seconds behind, however Odin acknowledges Loki's tricks and sentences him once again to the land of the trolls, while declaring Thor the victor.

Loki's next attempt at destroying Thor takes place in the episode "The Absorbing Man". As the title implies, Loki creates the Absorbing Man by bestowing an escaped convict Carl "Crusher" Creel with the ability to absorb the properties of anything he touched. Loki learned the nexessary skill to achieve this after studying with Ularik the warlock; when Loki grows tired of serving the warlock he uses a special mist to keep him in suspended animation and to make it look as it was one of his own experiments gone wrong that caused all this. The Absorbing Man is sent by Loki to Earth, where he confronts the cops that were chasing him before he gained his super-powers, and then also the mighty Thor. After a long fight in which Crusher absorbs a lot of elements - even Thor's enchanted Uru hammer, but is unable to hold on to it and once he lets go of the hammer his body retruns to its original form - the villain tries absorbing all the elements Earth contains, turning into a giant in the process. Thor then defeats him by causing a chemical reaction which results in a nuclear explosion, and the Absoring Man turning into the single element Helium, drifting harmlessly into the atmosphere.

In "To Kill a Thunder God", the Norn Queen asks Odin to return her magical Norn Stones which Loki has stolen (and used in a previous episode); Odin is prepared to enter the Odinsleep - he must sleep for an entire day to replenish his strength, so he sends Thor on a quest to recover the magical items which Loki has apparently hidden somewhere on Earth. Thor finds the Norn Stone very close to the tomb of the Destroyer, an enchanted and unstoppable suit of armor Odin has defeated previously and banished there. Loki manipulates a hunter to shoot Thor with a tranquilliser gun (which although briefly, affects Thor) and then enter the forbidden tomb and approach the Destroyer. Once he is close enough the suit of armor drains the life force of the human and awakens, leaving the body of the hunter a lifeless statue. Thor confronts the Destroyer, but the latter proves to be more than a match for the Thunder God. Loki is proud of what he has achieved but is soon informed by the Norn Queen that Odin has vowed that he would kill whoever would re-activate the Destroyer. Realizing that if Thor dies in this fight it would also mean his death, Loki tries asking for help from other Asgardians yet nobody would believe him after all the tricks he has pulled in the past and his past attempts at destroying Thor. The Destroyer manages to cut Thor's hammer in half with a bolt of energy (though the hammer will be intact in the next scenes without any explanation) and fires a similar bolt at Thor, which could have destroyed him but since he was carrying the Norn Stones at that moment, only make Thor immaterial - but is saved and made solid again by Loki, who uses most of his powers to save his brother. The Destroyer is defeated when Thor approaches the body of the hunter and mentions that the soul transfer would only last one hour before the hunter's life force will return to his mortal body. After stopping the armor Thor brings the magical stones back to the awakened Odin, who claims that Loki must be punished - and the punishment chosen this time is for him to serve the Norn Queen for a goodly period.

Loki briefly appears in the next episode ("The Grey Gargoyle"), enjoying the arguement between Thor and Odin concerning the former's feelings for the mortal Jane Foster.

In "Every Hand Against Him", Loki returns to Earth and under the guise of a human pays the bail for two of Thor's rogues - Mr. Hyde (who was defeated by Thor in the previous episode) and Cobra. Loki increases their powers and sends them to kidnap nurse Jane Foster, knowing that Thor won't risk putting her life in danger by attacking them directly. He then shows Odin what is happening on Earth and tricks him into believing Thor has become a coward, by letting criminals escape and furthermore continues to defy Odin by loving Jane. Odin then decides to banish Thor from Asgard; when Thor returns to confront Loki, he is attacked by pretty much every other Asgardian there - but obviously he manages to escape. On Earth, Thor battles Mr. Hyde and Cobra and their fight is interrupted by an explosion in which Jane is badly injured. Thor creates a time warp to keep her alive while he finishes the battle. Odin decides on helping Thor and sends Loki with a message to Hardol the Healer, who will prepare the potion Jane needs to survive. Loki has no intention on helping his half-brother but is intercepted by Balder who delivers the message instead, and brings the potion to Thor.

Loki's final appearance on the show is in the episode "The Tomorrow Man". In the first act of the story, Zarrko the Tomorrow Man travels from the 30th century to our time to steal a nuclear bomb he plans on using to rule the world of the future. Thor follows him into his time and manages to defeat him; their fight leaves Zarrko with amnesia. Back in our time Thor is punished by Odin for refusing to give up on Jane Foster - the punishment being that his power is now reduced by half. Seeing this as an opportunity to finally get rid of Thor, Loki uses the Well of Centuries to contact Zarrko and restore his memories of how Thor defeated him. Zarrko returns to our time with a giant robot - which can't be destroyed by the weakened Thor. The villain promises to leave if Thor will agree to join him in the 30th century, as his slave. Thor reluctantly agrees, but Odin is angered that one of his sons will be a slave and restores his full powers, which enable Thor to defeat Zarrko yet again and safely return home.

All in all, Loki's first animated appearances were pretty good - the stories are more or less faithful adaptations of the classic comics, and I find them entertaining enough. The only complaints I really have are that he was used too much on the show and that his voice was a little too high pitched. Next part: Loki on Spider-Man and his Amazing Friends, Hulk Vs. and Thor: Tales of Asgard!